Assuming the following reaction proceeds in the forward direction,
3 Sn4+(aq) + 2 Cr(s) 3 Sn2+(aq) + 2 Cr3+(aq)
a. Sn4+(aq) is the reducing agent and Cr(s) is the oxidizing agent.
b. Cr(s) is the reducing agent and Sn2+(aq) is the oxidizing agent.
c. Sn4+(aq) is the reducing agent and Sn2+(aq) is the oxidizing agent.
d. Cr(s) is the reducing agent and Cr3+(aq) is the oxidizing agent.
e. Cr(s) is the reducing agent and Sn4+(aq) is the oxidizing agent.
answer A
Oxidized: lost electrons, became more positive.
a) Cr is oxidized, so it is the reducing agent. Sn4+ gains electrons, so it is reduced, so it must be the oxidizing agent.
So a is not the asnwer
To determine which species is the reducing agent and which is the oxidizing agent, we need to compare the oxidation states of the species before and after the reaction.
In this reaction, the oxidation state of Sn is changing from +4 to +2, while the oxidation state of Cr is changing from 0 to +3.
A reducing agent is a species that is being oxidized (losing electrons), and an oxidizing agent is a species that is being reduced (gaining electrons).
In this case, Sn4+(aq) is being reduced (its oxidation state is decreasing from +4 to +2), so Sn4+(aq) is the oxidizing agent.
On the other hand, Cr(s) is being oxidized (its oxidation state is increasing from 0 to +3), so Cr(s) is the reducing agent.
Therefore, the correct answer is e. Cr(s) is the reducing agent and Sn4+(aq) is the oxidizing agent.
To determine the correct answer, we need to understand the concepts of oxidation and reduction.
Oxidation refers to the loss of electrons by a species, while reduction refers to the gain of electrons by a species. In a redox reaction, there is an exchange of electrons between two species. The species that undergoes oxidation is called the reducing agent, as it causes the reduction of another species by donating electrons. The species that undergoes reduction is called the oxidizing agent, as it causes the oxidation of another species by accepting electrons.
In the given reaction, we have Sn4+(aq) and Cr(s) as reactants. Sn4+(aq) is a cation with a +4 oxidation state, while Cr(s) is the element chromium in its solid state. Since Sn4+ has a positive charge, it means that it has lost 4 electrons and is in an oxidized state. On the other hand, Cr(s) is in its elemental form and is not charged, indicating that it has not lost or gained any electrons.
In the products of the reaction, we have Sn2+(aq) and Cr3+(aq). Sn2+ is a cation with a +2 oxidation state, which means it has gained 2 electrons and is in a reduced state. Cr3+ is a cation with a +3 oxidation state, indicating that it has lost 3 electrons and is in an oxidized state.
From the above analysis, we can conclude that Sn4+(aq) is the reducing agent in this reaction because it donates electrons and causes the reduction of Cr(s) to Cr3+. Therefore, the correct answer is:
a. Sn4+(aq) is the reducing agent, and Cr(s) is the oxidizing agent.